The computing system of the General Clinical Research Center (GCRC) will be utilized to store and analyze the data base of Studies of Left Ventricular Dysfunction (SOLVD), a clinical trial of 6700 patients with reduced ejection fraction (2500 symptomatic and 4200 asymptomatic) at 23 centers, randomized to treatment with angiotensin converting enzyme (ACE) inhibitor or placebo, with up to 5 years of follow-up. Additionally, we will continue our analysis of the SOLVD radionuclide ventricular function substudy. The SOLVD data base and the SOLVD radionuclide ventricular function database contain a wealth of information for further analysis of questions related to clinical heart failure in general, and the response to ACE inhibitor treatment in particular. Our aim is to pursue current and future questions that can be approached from this database. This is a "Computer Only" study.